/**
 * @param {number[][]} matrix
 * @return {void} Do not return anything, modify matrix in-place instead.
 */
 var setZeroes = function(matrix) {
  let m = matrix.length
  let n = matrix[0].length
  if(m==0) return []
  let i
  for( i=0;i<m;i++){
    if(matrix[i][0] == 0) matrix[i].fill(0)
  }

  for(i = 0;i<n;i++ ){
    if(matrix[0][i] == 0) matrix[0][i].fill(0)
  }
};
